TRENTON, N.J. (CBSNewYork/AP) — Twenty-nine bars and restaurants – nearly half of them TGI Fridays – are in trouble with the State of New Jersey for allegedly filling top-shelf liquor bottles with lower-quality spirits and fooling customers.

As 1010 WINS’ Holli Haerr reported Wednesday, a yearlong investigation by the state Division of Alcoholic Beverage Control, dubbed “Operation Swill,” found that the establishments had swapped out the good liquor in an effort to fool customers and increase profits. The customer paid for the premium brand, but was instead, unbeknownst to the customer, poured the non-premium brand.

The enforcement action was executed by more than 100 state investigators. It stems from citizen complaints, confidential informants, and new technology used to test samples taken covertly from the establishments.

Thirteen of the restaurants cited are TGI Fridays located in central and northern New Jersey. CBS 2 went in with a hidden camera at a TGI Friday’s on Route 3 in Clifton that was cited, finding business as usual.

Also cited was an Applebee’s in Kearny, which Steven Rodriguez said he frequently visits.

“That’s like basically stealing from people right there,” he said.

Rodriguez and others who frequent the Applebee’s said it is a bad deal for customers who drink.

“It’s definitely not good to hear, especially if you’re expecting something top shelf and you’re getting lower quality,” added Katharina Young of Wallington, N.J.

The investigation, the result of citizen complaints, used confidential informants and covertly obtained samples that were tested.

State officials would not say what types of premium brand liquor got swapped out with lower-quality spirits the most, but did say inventory was seized and records were sought as part of the probe.

A TGI Fridays representative provided the following statement on Wednesday:

“TGI Fridays was just made aware of this issue and is working closely with the franchisee and owner of the cited locations to review and investigate these serious allegations. We have one of the most extensive bar and beverage programs in the industry, which sets a very high standard in the quality and service of our beverages.”

The Briad Group said it opened its first TGI Fridays in New Jersey in 1993. A call to the Briad Group seeking comment was referred to TGI Fridays.

“Now that I know it’s going to be different, I’ll go somewhere else, definitely,” said Alex Tsoi of Hasbrouck Heights.

“You’re not getting your money’s worth,” added Sorrentino. “In this day and age you need that, you need your money.”